2. DNA/RNA

3. Protein

Description

The mRNA encodes a 47.3 kDa protein consisting of 474 amino acids.

Expression

SOX4 appears to be fairly ubiquitously expressed at low levels in most adult tissues, with high levels found mostly in T lymphocytes. Its expression is up-regulated in many cancer types relative to benign tissue of origin (Rhodes et al., 2004).

SOX4 is part of a family of Sox transcription factors that share significant homology. SOX4 is in the Group C Sox homology group that includes SOX11, SOX22 and SOX24. SOX4 shares the highest degree of homology with SOX11 (Bowles et al., 2000).

MicroRNA miR335 has been shown to regulate Sox4 levels and is frequently found lost in primary tumors of breast cancer patients who relapse (Tavazoie et al., 2008). In experimental model systems, it appears that SOX4 is a primary gene product associated with metastasis and migration.

SOX4 is upregulated is a significant percentage of lung cancers (Bangur et al., 2002; Friedman et al., 2004) and antibodies to this protein can be found in the serum of lung cancer patients (Friedman et al., 2004).

Experimental manipulation of SOX4 in hepatocellular carcinoma cell line models suggests that SOX4 is pro-apoptotic in this tumor type (Ahn et al., 2002). Paradoxically, another group found that knocking down SOX4 expression in a hepatocellular carcinoma cell line decreased tumorigenicity (Liao et al., 2008).

SOX4 has been show to be over-expressed in prostate tumor samples by microarray analysis, real-time PCR and immunohistochemistry. Additionally, stable transfection of Sox4 into non-transformed prostate cells form colonies in soft agar, suggesting SOX4 can be a transforming oncogene.